Renal
cholesterol embolization can occur spontaneously or as a complication of aortic surgery or major vessel angiography in patients with diffuse
atherosclerosis. The demonstration of characteristic
cholesterol crystals in tissue biopsy specimens is a pathognomonic finding. However, renal
cholesterol embolism may be clinically diagnosed when
renal failure develops after known inciting factors or together with systemic manifestations of atheromatous embolization such as lower extremity
livedo reticularis, focal digital
ischemia or
retinal embolism. Previous investigators have emphasized the progressive nature of
renal insufficiency due to
cholesterol embolism, its poor prognostic significance and almost uniformly fatal outcome. In this report, we describe five additional patients with renal
cholesterol embolization. In three of them only moderate
renal insufficiency developed, and kidney function subsequently improved in all. In two patients the condition progressed to
end-stage renal disease; one died with
chronic renal failure whereas the other patient required four months of
hemodialysis before kidney function eventually improved. Thus,
cholesterol embolization may produce a spectrum of renal functional impairment. In some patients there is only a moderate loss of renal function with subsequent improvement; in others
renal failure ensues. In this latter group, eventual return of kidney function can occur even after a prolonged period of
renal insufficiency.